Shock absorber



March 15, 1927. 1,621,261

L. l.. LOMAR SHOCK ABsoRBER Filed NOV-11. 1925 z sheets-sheet 1 1 y1,621,261 March 15, 927 L. L. LOMAR sHocK ABsoRBER Filed Nov. 11. 1925 2 sheets-Sheet 2 :jwuew *op lalala' lama?" atto/Luau ffl Patented lVlar. 15, .1927.

' UNITED STATES 1,621,261 lPaTfF..-1-JT Y, OFFICE.

LOUIS L. LOMAR, 0F HOUSTON, TEXAS;y

SHOCK ABSOBBER.

Application led November 11, 1925. Serial No. 68,420.

'within a fluid containing cylinder. In devices of this character it ,is usual to provide for escapeo'f a'portion of the 'fluid subjected to compressive action of the piston from one side: of `the piston to the'other.-

This is ordinarily by means of valved or otherwise restricted passages through or around the piston. v l

In certain of the VWell-known constructions an aperture is formedin the piston and in some instances a valve controls the passage of fluid through'such aperture. Different types and arrangements of' valves have been employed in an effort to regulate the fiow of liquid in such manner as will adequately and properly cushion the stroke of the piston in one or both directions.

.Considerable difficulty has been experienced in` determinin the properlocation and size of the fiui passages and in devising regulating meanswhich will be adequate and effective under all conditions. The devices heretofore employed have been open to the objection that they were difficult and expensive to manufacture or that they were incapable of properly regulating the lflow of fluid or could not be readily adjusted to accommodate varying operating conditions, with different cars, different loads, and other varying factors.

The principal object of my invention is to provide a shock absorber of this general type with efficient means controlled by movement of the piston for regulating the speedy of movement .of the piston and cushioning its action.

Another object of my invention is a shock absorber of the piston type which is simple in construction and comparatively easy. to manufacture and which may be readily adjusted for vdifferent operating conditions while the device is in 'position upon an automobile.`

Still further objects are the provision lof means for properly controlling and regulating the action of the shock absorber during the shock andthe rebound, and of' readily accessible means for adjusting the device to accommodate varying conditions.

Figurel of the drawings is a vertical section through the shock absorber.

F'gure 2 is a view, partlyin section, taken at right angles to the view shown in Figure 1. 7

Figure 3 is a section taken on the line 3-3 of Figure 1.

Figure 4 is a top view of the shock K absorber.

Figure 5 is a view similar to that shown in Figure 3, but with the valve shown in -sli htly different position, vand igure is a vertical section of a modified form of my invention. The' device which constitutes my present invention comprises a cylindrical casing 1,

closed at its respective ends by caps' 2 and'` 3, and adapted to contain oil or other fluid, a piston 5, `within the casing, anda hollow piston rod 10, slidable through an opening 45 in cap 2. Escape of fluid throughv this opening is prevented b the usual bushing 18, packing 19, and pac ing nut 20.

The casing 1 andthe hollow piston rod l() are adapted to be secured to relatively movable parts of a vehicle. In the preferred adaptation of my device the casing is provided with a bracket 40 whichl may be made integral with the cap 3, and which carries a socket'member 22 of a ball and socket joint by means of which the casing may be attached to the axle of themvehicle. The piston rod 10 may be connected by a similar universal joint to the frame of the vehicle, a suitable ball member '23 being fitted upon the end of the piston rod for this purpose. f l

In the forni of my device shown in Figures 1 to 5, inclusive, the casing 1 and its *ca'ps 42 and 3- are held tightly together by screws 4 whichpass through apertures in the piston 5 and serve to guide the piston in its movement and prevent it from turning.

The piston 5 divides. the interior of the casing l into chambers 7 and 8. Passage of fiuid ast this piston from one chamber to the ot er is prevented by a packing ring 6. The inner end of the piston rod 10 is screwthreaded', as at 42, and extends through a central opening in the piston 5 and is secured thereto by a nut 41. By means of apertures 14 formed in the walls of the piston rod 10 and.comm`unicatinfr with its central' bore 46, restricted assage tor fluid is provided between ,fluid .c iambers 7 and 9 is flattened and tapered, as at 15 and 15, the width of each flat portion tapering from the base of the valve t'o its free end (see Figures 1 and 2). The valve or valve rod 9 is so supported as to be adjustable from the exterior of the casing, its screw-threaded head 16 being screwed into a screw socket in cap 3 and held in adjusted position by a locknut 17. The valve 9 may be adjusted by turning screwhead 16, and thus var ing the angular position fof the faces 15 an( l5 relative to the openings 14. The valve 9 1s shown in fully open position in Figure 3 and in partially closed position in Figure 5.

Increased flowv of fluid through the piston in one direction is provided for by passages 13, controlled by ball check valves 11, retained in alignment-with said a collar 12 on piston rod 10.

In the operation ofthe device shown 1n Figures 1 to 5, inclusive, when the vehicle wheels strike'an obstruction or elevation 1n the road, the vehicle frame descends,-carry ing with it piston rod 10 and moving piston 5 downwardly toward cap 3. Downward movement of the pistonl is retarded by the liquid in chamber 8, whichv is gradually forced into chamber 7, princi ally through openings 13. lOn the rebound rom the compression of the vehicle spring, piston 5 is drawn upwardly against the reslstance of the body of fluid in chamber 8. In this d1- rection of movement of the' piston the open ings 13 are closed by valves 11, and Huid can pass from chamber, 7 to chamber 8 only through openings 14 and bore 46. This restricted passage retards the upward movement of the piston. The passage' of fluid vthrough openings 14 willbe--further retarded lby valve 9 andfby reason of the tapered formv of this valve, the retarding action will gradually increase as the piston moves toward cap 2 and the larger or free end of the valve or valve rod 9. In this way the rebound action is gradually' checked. Where conditions are such as to make it desirable to vary the degree of checking action, the flow of fluid through o enings 14 maybe regulated by turning tlie screw head 16 of the lvalvein either direction, to control the flow ,through the openings 14, the retarding action being greater when the valve is in a position partiell closing openings 14 (as in Figure 5) t an when it is in fully open ition (as in Figure 3). Thus, the veicle springr is under definite'control at all times,'a`nd `this control may be regulated and altered toaccord with xarying conditions control valve 9, without by meansl'of an exterior `ad'ustment of the l Vismantling the device or'removingany part of it vfrom 'the vehicle. 1

In the modified 'form of the device illustrated inFigure 6, the construction and arrangement of the casing, piston, and piston openings by rod and adjustable tapered valve are the Same as in the form shown in Figures 1 to 5, inclusive.

In the Figure 6 device,- however, the guide members 44 are tubular, and provided with 'a series of openings 28 so placed that they will be covered or uncovered seriatim by the pist-on during a portion of its movement. The interior of the tubes 44 is also in communication with chambers 7 and 8 through openings 29 and 26, each of which is preferably of greater size than any of the openings 28. Passage ofv fluid through the conduitsV 24 of the tubes 44 is controlled by check valves 25 in valve chambers 27 Screws and 31 extend through casing caps 2 and 3, respectively, and engage the threaded end Vportions of guide members 44 to retain the latter in position and clamp the caps 2 and 3 upon the casing 1. Screws 30 also serve lto close the chambers 27 and retain the valves 25.

The operation of the Figure 6 form of my device is enerally similar to that of the Figure 1 orm. On the downward stroke of` the iston 5, liquid is forced from chamber 8 t rough openings'28, conduit 24 andl openings 26 into chamber 7. Some liquid may also pass out of the chamber through bore 46 and openingsA 14. In the course of the downward stroke of the piston it irst closes the uppermost of the openings 28, compelling the liquid to flow through the openings remaining uncovered. As the piston continues downwardly, the other openings 28 4are successively covered. In this way the `flow of li uid from chamber 8 is gradually decrease and the resistance to downward movement of the piston is correspondingly increased, with the result that the shock which impels the piston downwardly isA gradually checked.

U on the rebound, the piston 5 moves upwar ly, exerting an upward pressure upon the liquid in chamber 7 and closing check valve 25. Since the liquid in chamber 7 canllO- not then pass through conduit 24, its escape ris limited to the restricted pastage through `openings 14 and the valve-controlled end of at its inner end'and' extending through, the y piston, saidpiston rod having an aperture 1n its wally.. a tapered valve rod adjustably mounted within said casing and extending within said hollow piston rod, said valve i rod having a portion of its 'surface flattened to prov1de for regulation of the passage of iluid through said'opening, said casing and said piston rod being adapted to Abe connected to relatively movable arts of a vehicle.

2. In a device of the c aracter described, a casing adapted to contain a fluid, a piston within said casing, a hollow piston rod open at its inner end and extending through said piston, said piston rod having an aperture in its wall, a tapered valve within said casing for controlling the passage of fluid through said aperture', one end of said rod extendin through an openingin said casing and axia ly adjustable -therein from the exterior of said casing, the other end of said valve rod extending within said hollow iston rod and having a portion of its sur ace cut away to rovide for regulation of the passage of fluid through said aperture, saidiston rod and said casing bein adapted to be connected to relatively Inova le parts of a vehicle. a

3.' In a device ofthe character described,

a casing adapted to contain a fluid, ariston within said casing, a' hollow piston ro open at its inner end extending through said piston and provided with an opening on the opposite side of said piston, atapered valve ad]ustably mountedfwithin said casing and extending Within said hollow piston rod, said valve having a portion of its surface flattened to provide for regulation vof the passage `of fluid through said opening, and

vguide rods secured within said casing and extending through suitable openings in said piston, there being a second passage for fluid rom one side ofthe piston tothe other and a check valve controlling said passage, said casing and said piston rod bein adapted to be connectedto relatively mova le parts of a vehicle. I

4. In a device of the character described, a casing adapted to contain a fluid, a piston within said casing, a hollow piston rod open at its inner end and extending through said piston, said piston rodhaving an aperture in its wall, a tapered valve adjustably mount ed within said casing and extending within said hollow longitudinal y tapered flat face to provide for regulation of kthe passage of fluid through said aperture, said piston rod and said casing being -adapted to be connected to relative] movable parts of a vehicle.

5. In a a casing adapted to contain a fluid, a iston within said casing, a hollow piston ro open at its inner end and extendin through said piston, said piston rodk having opp'ositely disposed apertures in its wall, a valve-mounted in said casing and axially adjustable therein, said 'valve extending within said hollow piston rod and having oppositely disposed' longitudinally tapered flat faces to provide Vfor regulation of the passage' of fluid through said oppositely disposed aperf tures. Y l

iston rod, said valve having a evice of the character described,-

6. In a device of the charactei` described, i

`a casing adapted to contain a fluid, a piston in said casing, a hollow piston rod vfopen at its inner end'and rovided with an opening on thel opposite si e of the piston, a ytapered valve rod adjustably mounted in said casing and extending within said hollowpiston rod, said valve rod having a: ortion of its `surface flattened to rovide or regulation of the passage of fluid) and hollow guide members secured Within said casing and extending through suitable openings in said piston, said guide members being provided with openings to permit passageof fluidy from one side of the piston to the other through said hollow guide members.

through said opening,

7. In a device. of the character described, l

a casing adapted to contain a fluid, a piston within said casing, means for operating said piston, said means and saidl casing being adapted to be connected to relatively movable parts of a vehicle, said piston having a passage therethrough, a by-pass lconduit within sai casing, a piston rod extending" through said casing, hollow guide rods extendfng through said piston and provided with a series of longitudinally spaced a ertures and a larger aperture closer to eac of its ends, a check valve controlling one of said larger apertures, said piston and said piston rod being adapted to be connected to relatively movable parts of a vehicle.

9. In a device of the character described a casing adapted to contain a fluid, said casing comprising an open-ended body portion and ca s therefor, a piston within said casing, a ho low piston rod open at its inner end and extending through said iston, said piston yrod, having an aperture 1n its wall, a valve adjustably mounted within said casing and extending within said hollow piston rod, said valve having a portion of its surface flattened, said flattened portion tapering longitudinally, hollow guide rods extending through saidl piston and provided with a series of longitudinally spaced a erturesand a larger aperture closer to eac of its ends, a check valve controlling one of said larger apertures, and screws extending through said' casing caps for securing said guide rods in position and clamping Said caps upon said casing.

10. In a device of th'e character described,

respectively o en and close said passage gradually as t e piston moves in opposite directions, yand a by-pass conduit in, said casing having an openin at one end thereof and a, series of longitu inally-spaced apertures toward the opposite end thereof adapted to be closed seriatim by movement of said piston.

11. In a device of the character described, a casing adapted to contain a fluid, a piston within said casing, means for operating said l piston, said means and said casinar being adapted to be connected to relatively movable parts of a vehicle, said piston having a passagetherethrough, a tapered valve Within said casing and extending Within said passage to gradually open and close said assage during movement of said piston, a yass conduit in said casing having a series of ongitudinally-spaced apertures adapted to be closed serlatim by movement of said piston, and a check valve for said conduit.

12. In a device of the character described,

l a casing adapted to contain a fluid, a piston within said casing, means for operating said piston, said means and said casing being adapted to be connected to relatively movable parts of a vehicle, saidiston having a passage therethrough, a va ve controlling said passage and arrangedito gradually open said passage during movement of the piston in one direction and to gradually close said passage during lnovement of the piston in the opposite direction, a by-pass conduit in said casing having a series of longitudinallyspaced apertures adapted to be covered seriatim by movement of said piston during its movement in the direction in which the passage through the piston is being opened, and a check valve for closing said conduit when the piston moves in the'opposite direction.. l

13. In a device of the character described, a cas'ng adapted to contain a fluid, a piston Within said casing, means for operating said piston, said means and said casing being adapted to be connected to relatively movable parts of a vehicle, saidpiston having a passage therethrough, a valve for said passage, atubular member extending through said piston andl provded with an opening I communicating with the interior of said casing at each end thereof and a series` o'f longitudinally-spaced apertures between said openings, said apertures being adapted'to be covered and uncovered seriatun 'by said piston to afford a varying resistance to movement of said piston during a portion of its stroke.

LOUIS L. LOMAR. 

